Check valve



FIG. 1 is a side perspective view of a swing check valve showing my new design;

FIG. 2 is a perspective view taken from the side opposite that shown in FIG. 1;

FIG. 3 is a perspective view taken from the side opposite that shown in FIG. 1 showing the valve in an open position;

FIG. 4 is a perspective view taken from the opposite side of FIG. 3;

FIG. 5 is an exploded perspective view taken from the side shown in FIG. 1; and

FIG. 6 is an exploded perspective view taken from the side shown in FIG. 2. 

The ornamental design for a check valve, as shown and described. 